Sweet's Syndrome in Acute Lymphoblastic Leukemia with t (9:22)

Sweet's syndrome (SS) is a rare disease diagnosed in children and is characterized by fever, erythematous skin lesions, and dense infiltration of neutrophils in the upper dermis without evidence of leukocytoclastic vasculitis on histopathology. It may occur secondary to infection, malignancy or drug intake. A case of a 9-year-old boy diagnosed as acute precursor B-cell lymphoblastic leukemia with BCR-ABL1 mutation and treated with induction chemotherapy and imatinib mesylate (IM) therapy is presented. After 8 weeks of consolidation chemotherapy, the patient developed painful and erythematous nodules where a biopsy showed dense neutrophilic infiltrate and edema in the papillary dermis consistent with SS. Whether SS is caused clinically by acute lymphoblastic leukemia, the presence of BCR-ABL1 mutation or due to IM therapy is discussed.